PLZZZ HELP ASAP THANKS : A round red ball is an example of

Physical change
Chemical change
Physical property
Chemical property

Explain why?

Thank you greatly appreciated!

7th grade question (easy) look at the diagram of the food web. the arrows mean eaten by. what would happen if the number of snakes went down? answer choices are in the image.

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).

Many organizations release indexes used to measure the development of the world's countries. as we learned in this lesson, these indexes measure many factors, from life expectancy to happiness. in your opinion, what are the three most important factors we can use to determine how developed a country might be? explain your answers in a few sentences.